Swansea City ran rampant over Sunderland on Saturday, scoring four goals in the second half to win, 4-0. The stark contrast between first and second periods showcased the Black Cats’ troubles in the back half.

Sunderland started brightly and nearly took the lead in the 13th minute, but Steven Fletcher could not put home a volley on a corner kick despite being unmarked. Especially in the first half, Sunderland strangled the midfield, at times playing with five players in the middle, taking away Swansea’s strong area.

Despite being out-possessed all match, the first half made Sunderland look like it had a chance to steal at least a point on the road. However, it all fell apart in the second half.

Saturday marked Gus Poyet’s first match as manager, and if the Uruguayan hopes to keep his new side in the Premier League beyond this season, he will have to shore up the back line and stop the constant flow of goals into the Black Cats’ net.

Bright first half

On defense, teams will normally draw two lines: a line of confrontation and a line of resistance. The line of confrontation is where a team will begin putting pressure on the ball, and it usually starts at about the midfield line to allow for compactness in defense.

The line of restraint is the point beyond which a team will not allow its opponent to pass. That line is much lower, usually 25 yards from goal or so, and it denotes the spot where delaying and keeping shape are no longer the concern, but winning the ball is everything.

All match at Swansea, Sunderland maintained a low defensive starting position. In the first half, the Black Cats drew their line of confrontation around midfield, but at times moved it higher, depending on the situation. The line of resistance stayed about 22 yards out, at the top of the “D” (the arc on top of the penalty area).

They also maintained proper numbers behind the ball and a proper defensive shape in their back four and midfield banks. They remained compact enough to make ball movement difficult, but not so compact as to negate counter-attacking opportunities and chances to win the ball high up the field.

Rarely should teams defend with more than one or two players extra (for example, five or six should be able to defend four) for the same reason. In the example above, Sunderland keeps eight players around the ball to defend Swansea’s seven in attack.

That changed drastically in the second half, allowing Swansea to maintain pressure for 45 minutes.

Painful second half

Because of Sunderland’s willingness to defend higher up the field in the first half, it rarely got pinned into its own end. However, comparing the location and frequency of interceptions between the first and second halves provides some idea of how that changed after the break.

Swansea possessed the ball through the middle more easily, and players turned and ran at goal in ways they could not in the first half. The reason for the radical change was dropping the line of confrontation, whether consciously or unconsciously, well into the Sunderland half for long periods of the half.

In this instance, Sunderland drops its bank of defensive and midfield players on top of its own 18-yard box, and the team has no discernible shape. Also, eight players are back to defend four attackers. Right from the kickoff, it was all hands on deck, hoping to hang on for the scoreless draw.

This screenshot is taken in the moments before Swansea took a two-goal lead. The space above the two deep lines of defensive players is open, where Michu (No. 3) is at this moment — close to the spot from which de Guzmán hits the goal.

Possession teams need to be put under pressure and made uncomfortable. Parking the bus only gives them more space to operate and combine to penetrate. Most of the Sunderland defenders backed off from the ball, putting too little immediate pressure on attackers to create any level of discomfort.

Corner kicks provide no respite

Two of Sunderland’s conceded goals were own goals off corner kicks, and they were nearly identical plays. It may have seemed coincidental at first, but a closer comparison reveals a pattern.

When defending corner kicks, most teams will put a player on the front post (some put one on the back post as well, but it’s a less dangerous space) and one in the near-post space about six yards off the goal line. The post defender is there to clear shots off the line, while the player in space is responsible for balls driven into the near side of the box, which is the most difficult spot for goalkeepers to cover.

When Sunderland sets up to defend both corners that end up in the goal, it has a man in the near-post space (red circles), but nobody on the front post itself (empty green circles). A free defender (yellow circle) is in the middle of the six-yard box as well, and some teams will station more than just one zonal defender in that area.

The rest are responsible for finding a man and marking him, contesting aerial balls and clearing the danger.

On both Sunderland own goals, Swansea attackers get into dangerous areas and cause scrambling defensive reactions. Because they are unable to track their marks, defenders end up running toward the goal to get goal-side of attackers.

The ball ends up in the back of the net despite defenders making contact first. Look at the spot where both balls cross the line: exactly where a front-post defender would be stationed. After one near-post goal, most teams would place a defender in that spot, but Sunderland does not. Goalkeeper Keiren Westwood has to organize his team more effectively.

Grim overall numbers

An inability to cope with pressure from other teams and a propensity to drop into a shell has led to an abysmal minus-15 goal difference overall for Sunderland, with little difference whether the game is at home (minus-6) or on the road (minus-9).

Falling deep into their half hasn’t allowed the Black Cats to attack, scoring just three goals at the Stadium of Light and two away from home. In turn, that has led to frustration for United States international Jozy Altidore, who continues to score for his country while remaining goalless in club play.

Sunderland’s defensive issues have progressively worsened over the last three seasons. If the situation does not reverse soon, the porous defense will be to blame for the club’s eventual relegation.

Liviu this was a phenomenal article and analysis of this game. Woeful defending is clearly the backbone of the Black Cats’ problems. They looked lost in the second half, and like you said, they looked ready to park the bus and take the draw.